Spinnerets



SPINNERETS Filed Feb. 29, 1952 yam '3 II. 'L'IIIIIIIIIIIIIIIIIJY/lIAZI'/IIIIIIIIIIAV/ United States Pa ent 2,742,667 SPINNERETS ClaudeClouzeau and Jean Etienne, Lyons, France, assignors to SocieteRhodiaceta, Paris, France, a company of France Application February 29,1952, Serial N 0. 274,266 Claims priority, application France November8, 1951 1 Claim. (Cl. 18-8) This invention relates to thick metallicspinnerets i. e. of a thickness greater than 1.5 mm., intended for themanufacture of all artificial or synthetic filaments, threads,horse-hair and the like.

A spinneret according to the invention is characterised in that each ofthe orifices in the spinneret comprises a. cylindrical part extendingfrom the out-side face of the spinneret and a coaxial inverted truncatedconical part whose large base is situated in the inside face of thespinneret, the height of the cylindrical part being less than 7 of thethickness of the spinneret, and the truncated conical part having anangle between the sides within the range of 15 to 60. The cylindricalpart can be either directly connected to the conical part or indirectlythrough an intermediate part formed by a figure of coaxial revolution,for example, a truncated cone whose height is less than 7 of the totalthickness of the spinneret which can be as much as, or greater than, mm.

The orifices of the spinnerets according to the invention are of a formwhich is particularly suited to obtaining a highly polished, practicallyglazed, surface condition over the whole extent of their walls. However,these walls can be given any other desired characteristic and inparticular they can comprise, hollowed or in relief, any figure or anydesign.

The spinnerets according to this invention are easier to start spinningwith than the spinnerets previously known, they are favourable to verysteady spinning of the materialbeing spun, and can be used longer whilstcontinuing to give products of excellent quality. They are, moreover,very simple to clean with the agents generally used.

The spinnerets according to the invention can be in the form of discs orof cups and comprise any number of orifices. They can be made of anymetal, for example, nickel, or chromium steel containing practically nonickel, but preferably they are made from a steel containing chromiumand nickel, for example 18% chromium and 8% nickel. Such steel hasexcellent resistance, both to the abrasion produced in the course ofspinning and to chemical attack occasioned either by the products spunor by the acids, for example, concentrated hot nitric or sulphuric acid,generally used for cleaning spinnerets. In particular, this resistanceis better than that of chromium steel containing no nickel or verylittle. Also, steel containing chromium, possibly nickel, and inaddition one or more other ingredients normally employed in thecomposition of steels called special such as for example, manganese,titanium, molybdenum, vanadium, copper or tungsten, may be used for themanufacture of these spinnerets.

The spinnerets forming the subject of the present invention can beutilised for the manufacture of all filaments, threads, horse-hairs etc.whether artificial or synthetic, particularly for those having a baseof: cellulose esters (especially cellulose acetate), polyvinylderivatives (especially polyvinylchloride, vinylchloride-vinyl acetatecopolymer, polyvinylcyanide), superpolycondensates (especiallysuperpolyamides, superpolyurethanes and superpolyesters).

" They are equally well suited for the dry or wet spinning of productsin solution or suspension and for spinning products in their meltedstate.

The invention is illustrated in the accompanying drawings, whereinz'Fig, 1 shows one orifice to an enlarged'scale;

Fig. 1A is a sectional view of a spinneret with a multiplicity oforifices according to Fig. 1;

Fig. 1B is a plan view of Fig. 1A;

Fig. 2 shows a second form of one orifice.

Fig. 2A is a sectional view of a spinneret with a multiplicity oforifices according to Fig. 2; and

Fig. 2B is a plan view of Fig. 2A.

The following examples, which are not limitative, are given so as tomake the invention more easily understood.

Example 1.32 orifices (one of which is shown in Fig. 1) spaced atregular intervals over a circumference of 30 mm. of diameter are piercedin a cup-shaped piece 1 of rustless steel containing 18% chromium and 8%nickel, of 2 mm. thickness. The piercing is done in such a way that eachof these orifices has the form represented in Fig. 1, i. c. it iscomposed of a cylindrical part2 united directly to a coaxial truncatedconical part 3 intended for reception of the product to be spun.

The cylindrical part 2 having a diameter of 0.08 is 0.06 mm. in height.

The angle between the sides of the truncated conical part 3 is 35 Thesespinnerets are particularly well suited to spinning a solution ofcellulose acetate in acetone.

Example 2.-l8 orifices (one of which is shown in Fig. 2) spaced atregular intervals over a circumference of 32 mm. diameter are pierced ina disc 1* of special steel containing 21% chromium, 7% nickel and 0.4%titanium, of 6 mm. thickness. This piercing is done in such a way thateach of these orifices has the form shown in Fig. 2, i. c. it comprisesa cylindrical part 2 joined through the intermediary of a coaxialtruncated conical part 4 to a truncated conical part 3 having the sameaxis, intended for the reception of the product to be spun.

The cylindrical part 2 of a diameter of 0.18 mm. is 0.15 mm. in height.

The truncated conical part 3 whose entry base diameter is 3.3 mm. has anangle between the sides of 25. The truncated conical part 4 joining thecylindrical part 2 to the truncated conical part 3- is 0.40 mm. inheight.

' These spinnerets are particularly well suited to spinning meltedsuperpolyamides.

What we claim and desire to secure by Letters Patent is:

A spinneret of the character described comprising a disk having flat andunobstructed inner and outer surfaces disposed parallel to each other,the said disk being of a uniform thickness throughout its area greaterthan 1.5 mm. and beingbored with a multiplicity of orifices extendingentirely throughthe said disk and spaced' from each other, the saidorifices being of duplicate formation and each consisting of a shortcylindrical outer end portion of small diameter leading from the outersurfaceof the disk and the height of which is less than A of thethickness of the disk, 21 main portion of inverted truncated conicalformation extending downwardly from the said inner surface in concentricrelation to the said cylindrical outer end portion for more than of thethickness of the said disk and at its lower end being of appreciablygreater diameter than the diameter of the cylindrical outer end portion,the angle between the sides of said main portion being between about 15and 60 and the length of said main portion being greater than itslargest diameter, and another inverted conical portion connecting saidmain portion with the inner end of the cylindrical portion the length ofwhich is greater than that of 3 the said cylindrical portion, but lessthan 5 of the 2,266,363 thickness of the said disk, the smallestdiameter of which 2,341,555 is equal to that of the said cylindricalportion, and the largest diameter of which is equal to the smallestdiam- 878 935 eter of said main portion. 5

References Cited in the file of this patent UNITED STATES PATENTSDreyfus May 6, 1924 10 Graves Dec. 16, 1941 Jones Feb. 15, 1944 FOREIGNPATENTS France Nov. 2, 1942

